High-density granulated detergent composition for clothes

ABSTRACT

The present invention is targeted to obtain a high-density granular detergent composition for clothes washing having sufficient detergency even when the amount of dosage is small without lowering its detergency even after long-term storage by blending a non-soap anionic surfactant and a crystalline alkali metal silicate in a state of non-contact as much as possible. The high-density granular detergent composition for clothes washing, the granular detergent composition having a bulk density of from 0.7 to 1.2 g/cm 3 , including (A) a non-soap anionic surfactant; (B) a crystalline alkali metal silicate; and (C) a metal ion capturing agent other than Component (B). In the above detergent composition, Component (A) is added in an amount of from 10 to 50% by weight, and a total amount of Component (B) and Component (C) is from 30 to 80% by weight, and a weight ratio of Component (B) to Component (C) is (B)/(C)=1/15 to 5/1, and at least a part of (B) the crystalline alkali metal silicate is blended in builder granules, the builder granules including the crystalline alkali metal silicate, a binder and optionally an aluminosilicate. Further, (A) the non-soap anionic surfactant is contained in the builder granules in an amount of less than 10% by weight.

TECHNICAL FIELD

The present invention relates to a high-density granular detergentcomposition for clothes washing. More specifically, the presentinvention relates to a high-density granular detergent composition forclothes washing undergoing little deterioration after long-term storageand exhibiting excellent detergency even when a small amount is used.

BACKGROUND ART

Moreover, to date, various kinds of chelating agents, ion exchangematerials, alkalizing agents, and dispersants have been known to be usedfor builders which are blended in detergents. Particularly, thephosphoric acid-based chelating agents comprising tripolyphosphates as amain component thereof have good water solubility and detergency, sothat they have been formulated as main detergent builder ingredients.

In recent years, however, the use of tripolyphosphates has beendecreased, since they are liable to cause eutrophication in closed waterareas such as lakes and marshes. Instead, crystalline aluminosilicates(zeolites) have been commonly used as substitutes for the metal ioncapturing agent, as typically disclosed in Japanese Patent Laid-Open No.50-12381, of which the disclosure is incorporate herein by reference.Such detergents formulating zeolites as mentioned above would require astandard amount of dosage of 40 g per one washing cycle, the washingcycle being most commonly using about 30 L of the washing liquid per onecycle in Japan. Also, the powder detergents available at that time had alow bulk density at a level of 0.20 to 0.45 g/ml owing to the solubilityin cold water. As a result, the standard volumetric amount is made ashigh as about 90 to about 200 ml of detergents per 30 L of water forwashing, so that distribution is cumbersome between shops andhouseholds.

Therefore, an intense investigation has been made to produce compactdetergents. For instance, Japanese Patent Laid-Open Nos. 62-167396,62-167399, and 62-253699, of which the disclosure is incorporated hereinby reference, disclose a remarkable decrease in the amount ofcrystalline inorganic salts such as sodium sulfate used as powderingaids conventionally contained in detergents. In addition, JapanesePatent Laid-Open Nos. 61-69897, 61-69899, 61-69900, and 5-209200, ofwhich the disclosure is incorporated herein by reference, disclose thatan increase in the bulk density of the detergents. By these findings,detergents having a bulk density of from 0.60 to 1.00 g/ml, whosestandard a concentration is from 25 to 30 g/30 L, can be produced,thereby resulting in making the detergents compact to a level of astandard volumetric amount of from 25 to 50 ml/30 L.

On the other hand, crystalline alkali metal silicates having particularstructure disclosed in Japanese Patent Laid-Open Nos. 5-184946 and60-227895, of which the disclosure is incorporated herein by reference,shows not only good ion exchange capacity but also the action of thealkalizing agents (alkalizing ability). Therefore, possibility of morecompact detergents has been studied because both of the functions whichconventionally have been satisfied by two different components,including metal ion capturing agents, such as zeolites, and alkalizingagents, such as sodium carbonate, can be satisfied with the abovecrystalline alkali metal silicates alone.

For instance, Japanese Patent Laid-Open No. 6-116588, of which thedisclosure is incorporated herein by reference, is concerned with adetergent composition containing a crystalline alkali metal silicate. InExamples of this publication disclosing a more compact detergent, evenin a case where the amount of the detergent composition at washing isreduced by 25% by weight, the detergent composition has a washing powersubstantially the same as conventional detergent compositions. However,the composition is formulated based on the conventional washingprinciple, wherein the mainstream of the technical idea has been to makethe oily components in dirt soluble by surfactants, and the compositionis obtained by simple replacement of the alkalizing agent and the ionexchange material with the crystalline alkali metal silicate. Therefore,the ion exchange capacity are ascribed solely to the crystalline alkalimetal silicates contained therein, so that the ion exchange capacity isinsufficient for that needed for detergent compositions. In this case,the functions of the crystalline alkali metal silicates as alkalizingagents are prioritized over their functions as metal ion capturingagents, so that the washing power of the detergent composition is notalways satisfactory, owing to the fact that the washing power of thedetergent composition is dependent upon the water hardness of water forwashing. Therefore, if the amount of dosage of the detergent compositionwere reduced, a good washing power is not able to be maintained.

A number of patent applications have been filed concerning thecrystalline silicates disclosed in Japanese Patent Laid-Open No.60-227895, of which the disclosure is incorporate herein by reference.Japanese Patent Unexamined Publication No. 6-502199, of which thedisclosure is incorporate herein by reference, discloses a detergentcomprising a layered crystalline silicate, a zeolite, and apolycarboxylate in particular proportions, to thereby provide adetergent which is free from providing film layer formation on fibersand has excellent washing power and bleaching agent stability. However,under the blending conditions given in this publication, when the amountof the detergents added was reduced at washing, the alkalizing abilityis deficient because the amount of the crystalline alkali metal silicatein the builder composition is small, thereby making it impossible tomaintain good washing power. Also, this publication never teaches thetechnical idea that an excellent washing power is exhibited in a smallamount of dosage of detergents.

The technical idea that an excellent washing power is exhibited in asmall amount of dosage of detergents as in the present invention cannotbe found for detergents containing crystalline alkali metal silicates(crystalline layered silicates) disclosed in Japanese Patent UnexaminedPublication 6-500141, Japanese Patent Laid-Open Nos 2-178398 and2-178399, each of which the disclosure is incorporate herein byreference. Rather, in the case where the amounts of the detergentcompositions shown in each of Examples are reduced, the washing power islowered.

Japanese Patent Laid-Open No. 7-53992, of which the disclosure isincorporate herein by reference, discloses that the amount of dosage percycle is reduced by formulating the layered crystalline silicatedisclosed in Japanese Patent Laid-Open No. 60-227895, together withother builder components such as alkalizing agents and metal ioncapturing agents, wherein the layered crystalline silicate is added inexcess to the builder components. The technical idea disclosed herein isa conventional idea simply rephrasing that the alkalizing agents and themetal ion capturing agents added as two components are substituted witha single component of the crystalline alkali metal silicate, neversuggesting any problems concerning a decrease in detergency afterlong-term storage.

In the prior art described above formulating the crystalline layeredsilicates, namely the crystalline alkali metal silicates, to thedetergent compositions, the compositions are not known to havesufficient detergency. Moreover, when large amounts of the crystallinealkali metal silicates are formulated in powder detergents comprisinganionic surfactants as the base surfactant components, the powderproperties after a long-term storage and the detergency are likely to belowered.

Accordingly, an object of the present invention is to provide adetergent composition for clothes washing exhibiting excellentdetergency and undergoing remarkably little deterioration after along-term storage.

These and other objects of the present invention will be apparent fromthe following description.

DISCLOSURE OF THE INVENTION

As a result of intense research in view of the above objects, thepresent inventors have found the relationship in an extremely simplewashing system between the conditions for washing clothes and thedetergency, and have developed a detergent composition showing excellentdetergency with a small standard amount of dosage by analyzing thereason for excellent detergency in a particular high alkali, low waterhardness washing conditions.

Specifically, while studying the washing liquid capable of showing gooddetergency, the present inventors have found that the higher the pH andthe lower the water hardness, the lower the dependency of the detergencyon the surfactant concentration, so that good detergency can beachieved. Also, in the case of a high pH but a high water hardness, thedetergency is drastically lowered even at a high pH. In the case ofwashing solely with a composition containing a surfactant withoutcontaining any alkalizing agents, although the detergency at low waterhardness is low, the dependency of the detergency on the water hardnessis sufficient small when compared to systems containing alkalizingagents. From these results, the present inventors have proceeded withtheir studies on the relationship between the washing liquid and thedirt stains.

The sebum dirt stains which are the most typical dirt stains adhered toclothes contain fatty acids and glycerides, and the dirt stains arepresumably a mixture of these organic materials with carbon, dirt, orpeeled keratin. In the case of a high pH, while the content of the fattyacids increases by hydrolysis of glycerides, the reaction of the fattyacids with alkali metals to form salts also proceeds. The alkali metalsalts of the fatty acids are soaps, and the salts of the fatty acidsbecome easily dissolvable in the washing liquid with the dirt stains bymaking the washing liquid alkaline. On the other hand, the salts of thefatty acids, which are alkali metal salts, are notably more easilyreactive with the calcium and magnesium ions in hard water as comparedto the reactivity with the fatty acids, and this reaction is acompetitive reaction with the freeing speed of the dirt stains in thewashing liquid. The fatty acids and the salts of the fatty acids reactwith the hardness-increasing components in the hard water to form a scumnot easily dissolvable in water, and the dirt stains are solidifiedwithout being freed from the interface of clothes and likely to be in astate not easily washed off. The scum formation rate becomes faster asthe alkalizing ability increases. For the reasons given above, in thecase where the pH is high and the water hardness is low, the washingliquids show excellent detergency, and in the case where the pH is highand the water hardness is high, the washing liquids show notably lowereddetergency. Also, in the case where an alkalizing agent is notformulated, because the sebum dirt stains are washed only with washingpower ascribed to the surfactants, the dependency of the detergency onthe water hardness become comparatively lower than the systemscontaining alkalizing agents.

From these observations, the present inventors have found that one ofthe methods for reducing the standard amount of dosage of the detergentsis to produce an environment of the washing liquid having low waterhardness and high pH to thereby prevent the scum formation as much aspossible, while utilizing the fatty acids in the dirt stains as soaps.Specifically, the present inventors have found a need to preparedetergent compositions of the present invention satisfy thecompositional requirements by having the crystalline alkali metalsilicate and other metal ion capturing agents in a particular blendingratio, each component being formulated in an amount of a particularrange.

Further, as a result of intensive studies in the development of desireddetergents, the present inventors have found that there is a tendencythat the detergency after a long-term storage is lowered in a case wherenon-soap anionic surfactants are used as base surfactants, the non-soapanionic surfactants being typically exemplified by sodiumalkylbenzenesulfonates most commonly formulated in powder detergents forclothes washing. The present inventors have found that the reasons forsuch lowered detergency are that the non-soap anionic surfactants arelikely to react with the crystalline alkali metal silicates.

Based on the above findings, the present inventors have found that theresulting high-density granular detergent composition for washingclothes shows sufficiently high washing power even with a small amountof dosage and shows substantially no decrease in detergency after along-term storage. The reasons for giving such effects are as follows:The crystalline alkali metal silicates and other metal ion capturingagents are blended in particular proportions in order to provide awashing liquid having a low water hardness and high pH. Also, thenon-soap anionic surfactants and the crystalline alkali metal silicatesare blended in a non-contact state as much as possible.

Specifically, the present invention is concerned with the following:

(1) a high-density granular detergent composition for clothes washing,the granular detergent composition having a bulk density of from 0.7 to1.2 g/cm³, comprising:

(A) one or more non-soap anionic surfactants;

(B) one or more crystalline alkali metal silicates; and

(C) one or more metal ion capturing agents other than Component (B),

wherein Component (A) is added in an amount of from 10 to 50% by weight,and a total amount of Component (B) and Component (C) is from 30 to 80%by weight, wherein a weight ratio of Component (B) to Component (C) is(B)/(C)=1/15 to 5/1, and wherein at least a part of the (B) crystallinealkali metal silicate is blended in the builder granules, the buildergranules comprising the crystalline alkali metal silicate, a binder andoptionally an aluminosilicate, and wherein (A) the non-soap anionicsurfactant is contained in the builder granules in an amount of lessthan 10% by weight;

(2) the high-density granular detergent composition for clothes washingdescribed in item (1) above, wherein a whole part of the Component (B)is blended in the builder granules:

(3) the high-density granular detergent composition for clothes washingdescribed in item (1) or (2) above, wherein the binder is at least onemember selected from the group consisting of polyoxyethylene alkylethers, fatty acids, fatty acid salts, and polyethylene glycols;

(4) the high-density granular detergent composition for clothes washingdescribed in any one of items (1) to (3) above, wherein the crystallinealkali metal silicates have SiO₂/Na₂O molar ratios of from 0.5 to 2.6;

(5) the high-density granular detergent composition for clothes washingdescribed in any one of items (1) to (4) above, wherein the buildergranules have an average particle size of from 250 to 1000 μm;

(6) the high-density granular detergent composition for clothes washingdescribed in any one of items (1) to (5) above, wherein the crystallinealkali metal silicates have an average particle size of from 1 to 50 μm;and

(7) the high-density granular detergent composition for clothes washingdescribed in any one of items (1) to (6) above, wherein the non-soapanionic surfactants are at least one member selected from the groupconsisting of linear alkylbenzenesulfonates, α-olefinsulfonates,α-sulfofatty acid salts, methyl ester salts of α-sulfofatty acids, alkylsulfates, alkenyl sulfates, and polyoxyethylene alkyl ether sulfates.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a graph of a calibration curve showing the relationshipbetween the logarithm of the calcium ion concentration and the voltage;

FIG. 2 is a graph showing the relationships between the amount of theCaCl₂ aqueous solution added dropwise and the calcium ion concentration;and

FIG. 3 schematically shows the production process of the paper containerused in storing the detergents in the working examples.

The reference numerals in FIG. 2 are as follows:

A is an intersection of the extension of the linear portion of Line Qwith the abscissa (horizontal axis); P shows the data of the blanksolution (buffer solution without using the chelating agent); and Qshows the data for the chelating agent-containing buffer solution.

BEST MODE FOR CARRYING OUT THE INVENTION

In order to achieve an excellent washing power, the washing liquidhaving a high pH and low water hardness needs to be produced.Specifically, the washing liquid has to satisfy the followingconditions.

(i) Containing metal ion capturing agents in amounts that the detergencyis not affected by the water hardness of the fatty acid in the dirtstains.

(ii) Containing an alkalizing agent capable of buffering at suitablyhigh pH.

From the aspect of having a high pH, the alkali metal silicates arepreferred. Here, sodium silicates such as JIS No. 1 and JIS No. 2usually used in detergents do not show metal ion capturing ability,while the crystalline alkali metal silicates are more preferred from theaspect of simultaneously satisfying both conditions (i) and (ii).However, there are some care needed even in cases where the crystallinealkali metal silicates are employed. This is because the alkalizingability increases as the amount of the crystalline alkali metal silicateincreases owing to its low water hardness. In such a case, it mayinevitably result in an undesirable increase in the exchanging speeds ofCa and Mg ions with the alkali metal ions of the fatty acid salts.Therefore, in order to satisfy more preferred conditions, it ispreferred that other metal ion capturing agents may be formulated in aparticular proportion, within which range the standard amount of dosageof the detergents can be effectively reduced without impairing itsdetergency.

Therefore, as the high-density granular detergent composition of thepresent invention, there can be included a granular detergentcomposition having a bulk density of from 0.7 to 1.2 g/cm³, comprising:

(A) one or more non-soap anionic surfactants;

(B) one or more crystalline alkali metal silicates; and

(C) one or more metal ion capturing agents other than Component (B),

wherein Component (A) is added in an amount of from 10 to 50% by weight,and a total amount of Component (B) and Component (C) is from 30 to 80%by weight, wherein a weight ratio of Component (B) to Component (C) is(B)/(C)=1/15 to 5/1, and wherein at least a part of said (B) crystallinealkali metal silicate is blended in builder granules, the buildergranules comprising said crystalline alkali metal silicate, a binder andoptionally an aluminosilicate, and wherein (A) the non-soap anionicsurfactant is contained in the builder granules in an amount of lessthan 10% by weight. By using the above detergent composition, the amountof dosage can be reduced without impairing detergency.

In addition, in order to obtain effective detergency against compositedirt stains, (A) the non-soap anionic surfactants are blended in anamount of from 10 to 50% by weight, preferably from 20 to 50% by weight,more preferably from 20 to 40% by weight, in the entire detergentcomposition. In addition, the weight ratio of Component (B) thecrystalline alkali metal silicates to Component (C) the metal ioncapturing agents other than Component (B) in the detergent compositionis (B)/(C)=1/15 to 5/1, wherein a total amount of Component (B) andComponent (C) in the entire detergent composition is from 30 to 80% byweight, preferably from 40 to 70% by weight. The amounts of (A) thenon-soap anionic surfactants, (B) the crystalline alkali metalsilicates, and (C) the metal ion capturing agents other than thecrystalline alkali metal silicates are most effective at the above givenranges. Also, the weight ratio of Component (B) to Component (C) is anessential feature in sufficiently exhibiting the effects of the presentinvention.

The preferred weight ratio of Component (B) to Component (C) is(B)/(C)=1/15 to 3/1, and still more preferred weight ratios may differdepending upon the initial water hardness of the washing liquid used.The water hardness of tap water greatly varies in different countriesand geographical circumstances throughout the world. For instance, whilethe tap water used for washing has a water hardness of usually around 4°DH in Japan, the tap water has as high a water hardness of 6° DH or morein the U.S., and that exceeding 10° DH in European countries. In thepresent invention, still more preferred ranges for the weight ratios areas follows. In the case where the water hardness is from 2 to 6° DH, theweight ratio of Component (B) to Component (C) is (B)/(C)=3/7 to 3/1; inthe case where the water hardness is from 6 to 10° DH, the weight ratiois (B)/(C)=1/6 to 4/3; and in the case where the water hardness is from10 to 20° DH, the weight ratio is (B)/(C)=1/15 to 1/1.

In the present invention, in addition to the above blending conditions,the following conditions must be satisfied. Specifically, at least apart, preferably 80% by weight or more of the entire crystalline alkalimetal silicate, more preferably a whole part, of the crystalline alkalimetal silicate is granulated using a binder, and the resulting granulesare formulated in the detergent composition as the builder granules.Also, the non-soap anionic surfactant is contained in an amount of lessthan 10% by weight, preferably less than 5% by weight, in the buildergranules. In the granular detergent composition of the presentinvention, the crystalline alkali metal silicate is substantiallynon-existent in the granule containing the non-soap anionic surfactant,sufficient detergency can be exhibited even after a long-term storage.The builder granules substantially comprise a crystalline alkali metalsilicate, a binder for granulating the crystalline alkali metalsilicate, and optionally a crystalline and/or amorphous aluminosilicate,such as zeolites. Besides the above ingredients, other ingredients canbe optionally blended to the builder granules, such ingredientsincluding fluorescent dyes, perfumes, commercially availableoil-absorbing carriers, such as silica compounds (for instance,“TIXOLEX” (manufactured by Kofran Chemicals) and “TOKUSIL” (manufacturedby Tokuyama Soda Co, Ltd.).

Builder granules prepared by granulating a crystalline layered sodiumsilicate, which is a crystalline alkali metal silicate, and/or a zeolitewith a binder and detergents formulating such builder granules have beenknown, as disclosed, for instance, in Japanese Patent UnexaminedPublication No. 6-502445, of which the disclosure is incorporated hereinby reference. In this publication, however, a non-soap anionicsurfactant is used as a binder, and in Examples of the publication, thenon-soap anionic surfactant is contained in the builder granules in anamount higher than that required, the builder granules containing thecrystalline layered sodium silicate. Here, the problem of the contactstate of the non-soap anionic surfactant and the crystalline alkalimetal silicate, as taught in the present invention, has never beensuggested. Moreover, the compositional requirement for reducing theamount of dosage of detergents is never suggested.

The binders usable in the builder granules are preferablynon-water-based binders, and the preferred examples thereof includepolyethylene glycols having a weight-average molecular weight of from3000 to 30000, nonionic surfactants exemplified below, and salts offatty acids. Highly preferred examples of the nonionic surfactantsinclude polyoxyethylene alkyl ethers which are ethylene oxide adducts ofalcohols, of which the alkyl moiety has 10 to 20 carbon atoms, whereinethylene oxide is added, in average, 4 to 10 moles. In a case where theamount of the crystalline alkali metal silicate contained in the buildergranules in an amount exceeding 20% by weight of the builder granules,the salts of fatty acids may be added in the form of fatty acids duringgranulation, whereby the fatty acids are subjected to neutralization ina solid state with the crystalline alkali metal silicate to form saltsof the fatty acids. Most preferably, the fatty acids and/or saltsthereof are used in combination with the nonionic surfactants, in whichcase the builder granules have excellent powder properties andsolubility. Besides Japanese Patent Unexamined Publication No. 6-502445mentioned above, the builder granules may be prepared by referring tomethods disclosed in Japanese Patent Laid-Open Nos. 6-10000 and5-209200, DE19529298, and W095/26394, each of which the disclosure isincorporated herein by reference. It is preferred that the resultingbuilder granules are coated by such surface coating agents asaluminosilicates.

Suitable compositional ranges for the builder granules are as follows(weight % being proportion in the builder granules):

Crystalline Alkali 10 to 80% by weight Metal Silicate Binder 10 to 40%by weight Aluminosilicate  0 to 40% by weight (calculated as anhydride)

It is preferred that the binder is one or more members selected from thegroup consisting of nonionic surfactants, fatty acids, salts of fattyacids, and polyethylene glycols. More preferably, the binder is one ormore members selected from the group consisting of polyoxyethylene alkylethers, fatty acids, salts of fatty acids, and polyethylene glycols. Thebinders may be blended in a weight ratio of polyoxyethylene alkylethers: salts of fatty acids (may be added in the form of fatty acids):polyethylene glycols of from 10:1:0 to 10:30:100.

It is preferred that the binder is added in a liquid state after heatingby spraying or adding dropwise to the powdery components. Also, aplurality of binders may be used in combination. For instance, a mixturecomprising two or more members-selected from nonionic surfactants,polyethylene glycols, fatty acids, and salts of fatty acids may be used.Particularly in the present invention, highly stable builder granulescan be preferably prepared by adding to the crystalline alkali metalsilicate the binders comprising polyoxyethylene alkyl ethers and fattyacids and optionally polyethylene glycols. This is because theneutralization reaction between the crystalline alkali metal silicateand the fatty acid takes place at the surface of the crystalline alkalimetal silicate, and the formed gel-like neutralized products, togetherwith other binder components, coat the surface.

The builder granules have an average particle size of preferably from250 to 1000 μm, more preferably from 350 to 600 μm. Also, thecrystalline alkali metal silicate has an average particle size ofpreferably from 1 to 50 μm, more preferably from 5 to 35 μm. Theparticle sizes of the builder granules and the crystalline alkali metalsilicate in the above ranges are particular suitable from the aspect ofobtaining good detergency even with a small amount of dosage and alsofrom the aspect of good powder properties and solubility providedthereby. The crystalline alkali metal silicate may be prepared to havethe above average particle sizes and particle size distribution bypulverizing the crystalline alkali metal silicate with such means aspulverizing mills, such as vibration mills, hammer mills, ball mills,and roller mills.

Since the required absolute amount of the metal ion capturing agentsvaries as the water hardness varies in different countries andgeographical circumstances as mentioned above, the standard detergentconcentration would be optimally adjusted accordingly.

Therefore, in cases where the initial water hardness differs in each ofthe washing liquids, the detergent concentrations are as follows:

1) As for the water for washing having a water hardness of 2 to 6° DH,the detergent composition has a concentration in the washing liquid offrom preferably 0.33 to 0.67 g/L, more preferably from 0.33 to 0.50 g/L.

2) As for the water for washing having a water hardness of 6 to 10° DH,the detergent composition has a concentration in the washing liquid offrom preferably 0.50 to 1.20 g/L, more preferably from 0.50 to 1.00 g/L.

3) As for the water for washing having a water hardness of 10 to 20° DH,the detergent composition has a concentration in the washing liquid offrom preferably 0.80 to 2.50 g/L, more preferably from 1.00 to 2.00 g/L.

Under these conditions, detergency equivalent or superior to that of theconventional detergents can be achieved in the high-density granulardetergent composition for clothes washing of the present invention.Also, the DH water hardness is easily measured by an ion coupling plasmamethod (ICP method).

Incidentally, excessively high pH is likely to be easily affected by thewater hardness, it is preferred that a maximum pH at 25° C. of thewashing liquid when adding the amount satisfying the above standarddetergent concentration conditions is not exceeding 11.5, preferablyfrom 10.5 to 11.2, more preferably from 10.7 to 11.0.

Here, the term “maximum pH of the washing liquid” in the presentinvention means the maximum pH value of the washing liquid obtained byadding a given detergent composition to distilled water at 25° C. underconditions that washing items are absent in the detergent solution.Specifically, the maximum pH is measured as follows. A given amount ofthe granular detergent composition is added and stirred in one liter ofdistilled water at 25° C., and the pH of the solution is measured usingsuch devices as a conventional glass electrode pH meter.

Each of the components will be explained in detail below.

(A) Non-Soap Anionic Surfactants

The non-soap anionic surfactants usable in the present invention referto anionic surfactants other than salts of fatty acids, and any of thoseusually used in detergents may be used. The non-soap anionic surfactantsmay be one or more members selected from the group consisting of linearalkylbenzenesulfonates, α-olefinsulfonates, α-sulfofatty acid salts,methyl ester salts of α-sulfofatty acids, alkyl sulfates, alkenylsulfates, and polyoxyethylene alkyl ether sulfates. Specific examplesthereof include linear alkylbenzenesulfonates, of which an alkyl moietyhas an average number of carbon atoms of 12 to 18; α-sulfofatty acidsalts or methyl ester salts thereof, each of which alkyl moiety has anaverage number of carbon atoms of 14 to 18; α-olefinsulfonates, of whichan alkyl moiety has an average number of carbon atoms of 12 to 18; alkylsulfates or alkenyl sulfates, of which an alkyl moiety or alkylenemoiety has an average number of carbon atoms of 12 to 22; andpolyoxyethylene alkyl ether sulfates, of which ethylene oxide moiety hasan average number of moles of 1 to 4. The alkali metal ions are mostsuitably used as counter ions of these salts from the aspect ofdetergency.

(B) Crystalline Alkali Metal Silicates

The alkali metal silicate usable in the present invention preferably hassuch an alkalizing ability, to a level that its maximum pH value is 11or more at 25° C. in a 0.1% by weight dispersion, and that it takes 5 mlor more of a 0.1 N HCl aqueous solution to lower its pH to 10 for oneliter of the above dispersion. Here, the alkali metal silicates arecapable of giving good ion exchange capacity as well as alkalizingability by making the alkali metal silicates crystalline, so that thestandard amount of dosage of the detergent composition can be evenfurther reduced. At least a part of Component (B) is formulated in thebuilder granules, and it is more preferred that the entire Component (B)is formulated in the builder granules.

The crystalline alkali metal silicates usable in the present inventionpreferably have SiO₂/M₂O molar ratios of from 0.5 to 2.6, wherein Mstands for an alkali metal atom. Also, the preferred ranges of theSiO₂/M₂O molar ratios are 1.5 to 2.2. The above molar ratio ispreferably 0.5 or more from the aspect of obtaining good ion exchangecapacity and hygroscopic property, and the molar ratio is preferably 2.6or less from the aspect of obtaining good alkalizing ability.Incidentally, the crystalline alkali metal silicates used in patentpublications discussed in BACKGROUND ART section of the presentinvention have SiO₂/Na₂O molar ratios (S/N ratio) of from 1.9 to 4.0.However, in the present invention, when the crystalline alkali metalsilicates having the S/N ratios exceeding 2.6 cannot have the effectsachieved by the present invention, thereby making it impossible toproduce detergents having washing power with a remarkable reduction inthe standard amount of dosage.

Among the crystalline alkali metal silicates usable in the presentinvention, a preference is given to those having the followingcompositions:

(1) xM₂O•ySiO₂ •zMe_(m)O_(n) •wH₂O,  (1)

wherein M stands for an element in Group Ia of the Periodic Table; Mestands for one or more members selected from the group consisting ofelements of Groups IIa, IIb, IIIa, IVa, and VIII of the Periodic Table;y/x is from 0.5 to 2.6; z/x is from 0.01 to 1.0; n/m is from 0.5 to 2.0;and w is from 0 to 20.

(2) M₂O•x′SiO₂ •y′H₂O,  (2)

wherein M stands for an alkali metal atom; x′ is from 1.5 to 2.6; and y′is from 0 to 20.

First, the crystalline alkali metal silicates having the composition (1)above will be detailed below.

In the general formula (1), M stands for an element selected from GroupIa of the Periodic Table, wherein the Group Ia elements may beexemplified by Na, K, etc. The Group Ia elements may be used alone, orin combination of two or more kinds. For instance, such compounds asNa₂O and K₂O may be mixed to constitute an M₂O component.

Me stands for one or more members selected from the group consisting ofelements of Group IIa, IIb, IIIa, IVa, and VIII of the Periodic Table,and examples thereof include Mg, Ca, Zn, Y, Ti, Zr, and Fe, which arenot particularly limited to the above examples. Here, a preference isgiven to Mg and Ca from the viewpoint of resource stock and safety. Inaddition, these elements may be used alone, or in combination of two ormore kinds. For instance, such compounds as MgO and CaO may be mixed toconstitute an Me_(m)O_(n) component.

In addition, the crystalline alkali metal silicates in the presentinvention may be in the form of hydrates, wherein the amount ofhydration (w) is usually in the range of from 0 to 20 moles of H₂O.

With respect to the general formula (1), y/x is preferably from 0.5 to2.6, more preferably from 1.5 to 2.2. From the aspect of anti-solubilityin water, y/x is preferably 0.5 or more. When the anti-solubility inwater is insufficient, powder properties of the detergent composition,such as caking properties, solubility, etc. are likely to be drasticallylowered. From the aspect of sufficiently functioning as alkalizing agentand ion exchange materials, y/x is preferably 2.6 or less.

With respect to z/x, it is preferably from 0.01 to 1.0, more preferablyfrom 0.02 to 0.9, particularly preferably from 0.02 to 0.5. From theaspect of the anti-solubility in water, z/x is preferably 0.01 or more,and from the aspect of sufficiently functioning as ion exchangematerials, z/x is preferably 1.0 or less.

With respect to x, y and z, there are no limitations, as long as y/x andz/x have the above relationships. When xM₂O, for example, isx′Na₂O•x″K₂O as described above, x equals to x′ +x″. The same can besaid for z when zMe_(m)O_(n) comprises two or more components. Further,“n/m is from 0.5 to 2.0” indicates the number of oxygen ions coordinatedto the above elements, which actually takes values selected from 0.5,1.0, 1.5, and 2.0.

The crystalline alkali metal silicate having the composition (1)consists of three components, M₂O, SiO₂, and Me_(m)O_(n). Materialswhich can be converted to each of these components, therefore, areindispensable for starting materials for producing the crystallinealkali metal silicates in the present invention. Here, known compoundscan be suitably used for starting materials for the crystalline alkalimetal silicates without limitations in the present invention. Examplesof the M₂O component and the Me_(m)O_(n) component include simple orcomplex oxides, hydroxides and salts of respective elements; andminerals containing respective elements. Specifically, examples of thestarting materials for the M₂O component include NaOH, KOH, Na₂CO₃,K₂CO₃, and Na₂SO₄. Examples of the starting materials for theMe_(m)O_(n) component include CaCO₃, MgCO₃, Ca(OH)₂, Mg(OH)₂, MgO, ZrO₂,and dolomite. Examples of the starting materials for the SiO₂ componentinclude silica sand, kaolin, talc, fused silica, and sodium silicate.

The method of producing the crystalline alkali metal silicate having thecomposition (1) may be exemplified by blending these starting materialcomponents to provide a desired composition in x, y, and z for thecrystalline alkali metal silicate, and baking the resulting mixture at atemperature in the range of preferably from 300 to 1500° C., morepreferably from 500 to 1000° C., still more preferably from 600 to 900°C., to form crystals. In this case, the heating temperature ispreferably 300° C. or more in order to sufficiently complete thecrystallization, which in turn makes it possible to maintain goodanti-solubility in water of the resulting crystalline alkali metalsilicate. The heating temperature is preferably 1500° C. or less inorder to prevent the formation of coarse grains which in turn makes itpossible to maintain good ion exchange capacity of the resultingcrystalline alkali metal silicate. The heating time is preferably 0.1 to24 hours. Such baking can be preferably carried out in a heating furnacesuch as an electric furnace or a gas furnace.

Next, the crystalline alkali metal silicates having the composition (2)above will be detailed below.

These crystalline alkali metal silicates are represented by the generalformula (2):

M₂O•x′SiO₂ •y′H₂O,  (2)

wherein M stands for an alkali metal atom; x′ is from 1.5 to 2.6; and y′is from 0 to 20.

Among them, a preference is given to the crystalline alkali metalsilicates having x′ and y′ in the general formula (2) such that eachsatisfies 1.7≦x′≦2.2 and y′=0, and those having a cationic exchangecapacity of preferably 100 CaCO₃ mg/g or more, more preferably from 200to 400 CaCO₃ mg/g, are usable. The above crystalline alkali metalsilicates are one of the materials having ion capturing ability in thepresent invention.

Since the crystalline alkali metal silicate in the present invention hasnot only good alkalizing ability and alkaline buffering capacity butalso good ion exchange capacity, the washing conditions are suitablyadjusted by formulating suitable amounts of the crystalline alkali metalsilicate.

A method for producing the above crystalline alkali metal silicates isdisclosed in Japanese Patent Laid-Open No. 60-227895, of which thedisclosure is incorporated herein by reference. However, the crystallinealkali metal silicates may be generally produced by baking glassyamorphous sodium silicate at a temperature of from 200 to 1000° C.Details of the production method is disclosed in “Phys. Chem. Glasses,7, 127-138 (1966), Z. Kristallogr., 129, 396-404(1969),” of which thedisclosure is incorporated herein by reference. Also, the crystallinealkali metal silicates are commercially available in powdery or granularforms under a trade name “Na-SKS-6” (δ-Na₂Si₂O₅) (manufactured byHoechst). Also, Japanese Patent Laid-Open No. 7-187655, of which thedisclosures are incorporated herein by reference, discloses acrystalline alkali metal silicate containing not only sodium but also aparticular amount of potassium.

The crystalline alkali metal silicate constituting Component (B) in thepresent invention has good alkalizing ability and alkaline bufferingcapacity as described above. In this aspect, the alkali metal silicatesare easily distinguished from the aluminosilicates, such as zeolites, inthe present invention. Also, when compared to sodium carbonate andpotassium carbonate, the alkali metal silicates have superior functionas alkalizing agents.

The crystalline alkali metal silicate in the present inventionpreferably has an ion exchange capacity of 100 CaCO₃ mg/g or more, morepreferably from 200 to 600 CaCO₃ mg/g. It is preferred that the amountof Si dissolved in water when stirred at 25° C. for 30 minutes ispreferably less than 110 mg/g, when calculated as SiO₂, particularly 100mg/g or less, from the aspect of obtaining good detergency in thepresent invention.

In the present invention, the crystalline alkali metal silicate havingthe general formula (1) and the crystalline alkali metal silicate havingthe general formula (2) may be used alone or in combination. It ispreferred that the total amount of the crystalline alkali metalsilicates is 50 to 100% by weight, more preferably 70 to 100% by weight,of the entire content of the alkalizing agents in the detergentcomposition, the alkalizing agents comprising crystalline alkali metalsilicates usable in the present invention and other alkalizers, such asalkali metal carbonates. From the aspect of aggressively acceleratingits self emulsification effects of the sebum dirt stains, the amount ofthe crystalline alkali metal silicate is preferably 50% by weight ormore.

In the present invention, as a silicate ingredient other than thecrystalline alkali metal silicates, amorphous alkali metal silicates,such as sodium silicates JIS No. 1, 2, and 3 may be used forbackbone-constituting ingredients of the spray-dried granules. However,in order to have an even lower standard amount of dosage per cycle, theamorphous alkali metal silicate may be actually contained in an amountof preferably 10% by weight or less, more preferably from 1 to 7% byweight.

(C) Metal Ion Capturing Agents Other Than Component (B). CrystallineAlkali Metal Silicates

The metal ion capturing agents other than the crystalline alkali metalsilicates in the present invention have a calcium ion capturing capacityof 200 CaCO₃ mg/g or more, more preferably 300 CaCO₃ mg/g or more. Inthe present invention, carboxylic acid polymers and aluminosilicate,such as zeolites, may be suitably used.

Examples of the polymers having ion capturing ability include polymersor copolymers, each having repeating units represented by the generalformula (3):

wherein X₁ stands for a methyl group, a hydrogen atom, or a COOX₃ group;X₂ stands for a methyl group, a hydrogen atom, or a hydroxyl group; X₃stands for a hydrogen atom, an alkali metal ion, an alkaline earth metalion, an ammonium ion, or 2-hydroxyethylammonium ion.

In the general formula (3), examples of the alkali metal ions includeNa, K, and Li ions, and examples of the alkaline earth metal ionsinclude Ca and Mg ions.

Examples of the polymers or copolymers usable in the present inventioninclude those obtainable by polymerization reactions of acrylic acid,(anhydrous) maleic acid, methacrylic acid, α-hydroxyacrylic acid,crotonic acid, isocrotonic acid, and salts thereof; copolymerizationreactions of each of the monomers; or copolymerization reactions of theabove monomers with other copolymerizable monomers. Here, examples ofthe other polymerizable monomers used in copolymerization reactioninclude aconitic acid, itaconic acid, citraconic acid, fumaric acid,vinyl phosphonic acid, sulfonated maleic acid, diisobutylene, styrene,methyl vinyl ether, ethylene, propylene, isobutylene, pentene,butadiene, isoprene, vinyl acetate (vinyl alcohols in cases wherehydrolysis takes place after copolymerization), and acrylic ester,without particularly being limited thereto. Incidentally, thepolymerization reaction is not particularly limited, and, any ofconventional methods can be employed.

Also, polyacetal carboxylic acid polymers such as polyglyoxylic acidsdisclosed in Japanese Patent Laid-Open No. 54-52196, of which thedisclosure is incorporated herein by reference, are also usable for thepolymers in the present invention.

In the present invention, the above polymers and copolymers preferablyhave a weight-average molecular weight of from 800 to 1,000,000, morepreferably from 5,000 to 200,000.

Also, in the case of copolymers, although the copolymerization ratiosbetween the repeating units of the general formula (3) and othercopolymerizable monomers are not particularly limited, a preference isgiven to copolymerization ratios of the repeating units of generalformula (3)/other copolymerizable monomer=1/100 to 90/10.

In the present invention, the above polymer or copolymer is contained inthe entire composition in an amount of preferably from 1 to 50% byweight, more preferably from 2 to 30% by weight, particularly from 5 to15% by weight.

In addition, a highly preferred example of (C) the metal ion capturingagents comprise: (C-i) the carboxylate, polymer mentioned above having aCa ion capturing capacity of 200 CaCO₃ mg/g or more; and (C-ii) analuminosilicate having an ion exchange capacity of 200 CaCO₃ mg/g ormore and having the following formula (4):

x″(M₂O)•Al₂O₃ •y″(SiO₂)•w″(H₂O),  (4)

wherein M stands for an alkali metal atom, such as sodium or potassium;x″, y″, and w″ each stands for a molar At number of each component; andgenerally, x″ is from 0.7 to 1.5; y″ is from 0.8 to 6; and w″ is from 0to 20, wherein the weight ratio of Component (C-i) to Component (C-ii)is (C-i)/(C-ii)=1/20 to 4/1, preferably 1/9 to 4/1. The total amount ofComponents (C-i) and (C-ii) Components preferably occupies 70 to 100% byweight based on (C) the metal ion capturing agent.

The aluminosilicates mentioned above may be crystalline or amorphous,and among the crystalline aluminosilicates, a particular preference isgiven to those having the following general formula:

Na₂O•Al₂O₃ •ySiO₂ •wH₂O,

wherein y is a number of from 1.8 to 3.0; and w is a number of from 1 to6.

As for the crystalline aluminosilicates (zeolites), synthetic zeoliteshaving an average, primary particle size of from 0.1 to 10 μm, which aretypically exemplified by A-type zeolite, X-type zeolite, and P-typezeolite, are suitably used. The zeolites may be used in the forms ofpowder, a zeolite slurry, or dried particles comprising zeoliteagglomerates obtained by drying the slurry. The zeolites of the aboveforms may also be used in combination.

The above crystalline aluminosilicates are obtainable by conventionalmethods. For instance, methods disclosed in Japanese Patent Laid-OpenNos. 50-12381 and 51-12805 may be employed, each of which the disclosureis incorporated herein by reference.

On the other hand, the amorphous aluminosilicates represented by thesame general formula as the above crystalline aluminosilicate are alsoobtainable by conventional methods. For instance, the amorphousaluminosilicates are prepared by adding an aqueous solution of alow-alkaline metal aluminate having a molar ratio of M₂O to Al₂O₃ (Mstanding for an alkali metal atom) of M₂O/Al₂O₃=1.0 to 2.0 and a molarratio of H₂O to M₂O of H₂O/M₂O=6.0 to 500 to an aqueous solution of analkali metal silicate having a molar ratio of SiO₂ to M₂O ofSiO₂/M₂O=1.0 to 4.0 and a molar ratio of H₂O to M₂O of H₂O/M₂O=12 to 200under vigorous stirring at preferably 15 to 60° C., more preferably 30to 50° C.

The intended product may be advantageously obtained by heat-treating awhite slurry of precipitates thus formed at preferably 70 to 100° C.,more preferably 90 to 100° C., for preferably 10 minutes or more and 10hours or less, more preferably 5 hours or less, followed by filtration,washing and drying. Incidentally, the aqueous solution of an alkalimetal silicate may be added to the aqueous solution of a low-alkalinealkali metal aluminate.

By this method, the oil-absorbing amorphous aluminosilicate carrierhaving an ion exchange capacity of 100 CaCO₃ mg/g or more and anoil-absorbing capacity of 80 ml/100 g or more can be easily obtained.See Japanese Patent Laid-Open Nos. 62-191417 and 62-191419, each ofwhich the disclosure is incorporated herein by reference.

Beside the ones mentioned above, examples of the metal ion capturingagents constituting Component (C) include aminotri(methylenephosphonicacid), 1-hydroxyethylidene-1,1-diphosphonic acid,ethylenediaminetetra(methylenephosphonic acid),diethylenetriaminepenta(methylenephosphonic acid), and salts thereof;salts of phosphonocarboxylic acids, such as salts of2-phosphonobutane-1,2-dicarboxylic acid; amino acid salts, such asaspartates and glutamates; aminopolyacetates, such as nitrilotriacetatesand ethylenediaminetetraacetates.

In a case where Component (C) is formulated in the builder granules,Component (C) in the form of the powdery materials may be formulated byblending it with the crystalline alkali metal silicate, whereinaluminosilicates may be optionally used as coating agents for thebuilder granules. Besides the above, Component (C) may be formulated inthe form of spray-dried granules prepared by adding inorganicsubstances, such as aluminosilicates and sodium sulfate and carbonates,and organic substances of Component (C), such as the polymer representedby the general formula (3), to give a slurry mixture, and spray-dryingthe resulting slurry mixture. As a matter of course, Component (C) maybe present in the granules other than the builder granules.

Components (B) and (C) are substances having metal ion capturingability. Here, the methods for measuring the ion capturing capability ofthe metal ion capturing materials depend upon whether the ion exchangematerials or the chelating agents are used for the metal ion capturingmaterials. The measurement methods for each of the materials in thepresent invention are given below.

Ion Exchange Material

The amount 0.1 g of an ion exchange material is accurately weighed andadded to 100 ml of a calcium chloride aqueous solution (500 ppmconcentration, when calculated as CaCO₃), followed by stirring at 25° C.for 60 minutes. Thereafter, the mixture is filtered using a membranefilter (made of nitrocellulose; manufactured by Advantech) with 0.2 μmpore size. The amount 10 ml of the filtrate is assayed for Ca content byan EDTA titration, and the calcium ion exchange capacity (cationicexchange capacity) of the ion exchange material is calculated from thetiter.

For instance, in the present invention, inorganic substances, such asthe crystalline alkali metal silicates and the aluminosilicates, such aszeolites, are measured as ion exchange materials.

Chelating Agent

The calcium ion capturing capacity of the chelating agent is measured bythe following method using a calcium ion electrode. Incidentally, thesolution used herein is prepared with the following buffer solution:

Buffer: 0.1 M—NH₄Cl—NH₄OH buffer (pH 10.0)

(i) Preparation of Calibration Curve

A standard calcium ion solution is prepared and voltage readings aretaken to prepare a calibration curve showing the relationships betweenthe logarithm of the calcium ion concentration and the voltage, as shownin FIG. 1.

(ii) Measurement of Calcium Ion Capturing Capacity

About 0.1 g of a chelating agent is weighed, and a 100 ml volumetricflask is charged with the chelating agent. The volumetric flask isfilled up to a volume of 100 ml with the above buffer solution. A CaCl₂aqueous solution (pH 10.0) having a calcium ion concentration of 20,000ppm calculated as CaCO₃ is added dropwise from a burette. The dropwiseaddition is made in an amount of 0.1 to 0.2 ml for each voltage reading.In addition, the buffer solution without containing the chelating agentis also subjected to the same dropwise treatment of the CaCl₂ aqueoussolution. This solution is called a “blank solution.” Thus, a calciumion concentration is calculated from the calibration curve given in FIG.1 by taking a voltage reading. The relationship between the amount ofthe CaCl₂aqueous solution added dropwise and the calcium ionconcentration is shown in a graph (FIG. 2). In FIG. 2, Line P shows thedata of the blank solution (buffer solution without using the chelatingagent), and Line Q shows the data for the chelating agent-containingbuffer solution. The point where the extension of the linear portion ofLine Q intersects with the abscissa (horizontal axis) is called “A.” Thecalcium ion capturing capacity of the chelating agent is obtained fromthe calcium ion concentration at “A” of the blank solution.

For instance, in the present invention, the polycarboxylates, such ascitrates, and carboxylate polymers, such as acrylic acid-maleic acidcopolymers are measured as chelating agents.

The high-density, granular detergent composition of the presentinvention comprises Components (A), (B), and (C) in particularproportions, wherein at least a part or a whole part of the crystallinealkali metal silicate constituting Component (B) is contained in thebuilder granules, and wherein the builder granules contain the non-soapanionic surfactant in an amount of less than 10% by weight. In suchhigh-density detergents, other ingredients may be optionally formulated.

One of the other ingredients which may be formulated in the granulardetergent composition of the present invention include nonionicsurfactants. The nonionic surfactants are usable as binders for thebuilder granules, and they may be formulated in granules other than thebuilder granules.

The nonionic surfactants are not particularly limited, and any ofconventionally known ones may be used. Examples thereof include thefollowing.

Polyoxyalkylene alkyl ethers, such as polyoxyethylene alkyl ethers andpolyoxypropylene alkyl ethers, polyoxyethylene alkylphenyl ethers,polyoxyethylene sorbitan fatty acid esters, polyoxyethylene sorbitolfatty acid esters, polyoxyethylene fatty acid esters, polyoxyethylenefatty acid alkyl esters, polyoxyethylene polyoxypropylene alkyl ethers,polyoxyethylene castor oils, polyoxyethylene alkylamines, glycerol fattyacid esters, higher fatty acid alkanolamides, alkylglycosides,alkylglucosamides, and alkylamine oxides.

Among these nonionic surfactants, a preference is given topolyoxyalkylene alkyl ethers, and greater preference is given toalkylene oxide adducts of alcohols, whose alkyl moiety has an averagenumber of carbon atoms of 10 to 18. The alcohols used herein may bepreferably primary or secondary alcohols, whose alkyl moiety may belinear or branched. Examples of the alkylene oxides include ethyleneoxide and propylene oxide. The alkylene oxides may be added in average,preferably from 4 to 10 moles.

The propylene oxide adducts preferably may be those added with 1 to 4moles of propylene oxide to a compound in which ethylene oxide ispreviously added in an average of 1 to 10 moles. The ethylene oxideadducts may include polyoxyethylene alkyl ethers, of which ethyleneoxide moiety has an average additional molar number of 10 or less.

More preferably, polyoxyethylene alkyl ethers which are ethylene oxideadducts of linear or branched, primary or secondary alcohols, of whichalkyl moiety has 12 to 14 carbon atoms and ethylene oxide is added, inaverage, 3 to 9 moles, more preferably 4 to 6.5 moles, particularlypreferably 4 to 6 moles. The nonionic surfactants may be included in thedetergent composition, at most 20% by weight, including the portionincluded in the builder granules.

Also, other surfactants such as fatty acids derived from beef tallow,palm oil, or coconut oil, and/or alkali metal salts of these fatty acidsmay be blended. When such surfactants are blended, they may beformulated in an amount of preferably 12% by weight or less, morepreferably from 0.5 to 8% by weight in the detergent composition of thepresent invention. Besides them, cationic surfactants, includingquaternary ammonium salts, such as alkyl trimethyl amine salts, andtertiary amines, and carboxy-type or sulfobetaine-type amphotericsurfactants, which are conventionally formulated in detergents, may beadded in amounts so as not to impair the effects of the presentinvention.

In the present invention, in a case where the nonionic surfactants, mostpreferably the polyoxyethylene alkyl ethers mentioned above, arecombinably used with other surfactant components in an amount of 5% byweight or more in the entire detergent composition, a furtherimprovement in detergency can be achieved by satisfying thecompositional weight ratio mentioned below. In other words, the mostpreferred detergent composition is such that the weight ratio of thecrystalline alkali metal silicate to the entire surfactants, excludingsoaps, cationic surfactants and amphoteric surfactants, is preferablyfrom 9/1 to 1/2, more preferably from 9/1 to 9/11.

Examples of other ingredients which may be added to the granulardetergent composition of the present invention include various saltsincluding alkali metal salts of chlorides, carbonates, and sulfites, andorganic amines, such as alkanolamines, besides amorphous alkali metalsilicates. In a case of making high the density of granular detergentcomposition by processing spray-dried particles, it is preferred thatsodium sulfate is blended as the backbone substance in the detergentcomposition, and sodium sulfate is blended in an amount of preferably 8%by weight or less, more preferably from 0.5 to 6% by weight. Also, theamorphous sodium silicates and the carboxylate polymers mentioned abovemay be also blended as the backbone substances.

In addition, color-fading preventives and anti-redeposition agentsgenerally blended in detergent compositions, including non-dissociatingpolymers such as polyvinyl alcohols, and polyvinyl pyrrolidones; organicacid salt builders, such as diglycolates and hydroxycarboxylates; andcarboxymethyl cellulose may be optionally used.

Besides the above, the following ingredients may be also contained inthe high-density, granular detergent composition of the presentinvention. For instance, caking preventives, such as loweralkylbenzenesulfonates whose alkyl moieties have about 1 to 4 carbonatoms, sulfosuccinates, talc, and calcium silicates; and antioxidants,such as tert-butylhydroxytoluene and distyrenated cresol, may be usedtogether with stilbene-type and biphenyl-type fluorescent dyes as inconventional methods. Also, blueing agents may be added, and perfumessuitable for high-density detergents disclosed in Japanese PatentLaid-Open Nos. 63-101496 and 5-202387, each of which the disclosure isincorporated herein by reference, may be also added. The kinds and useof these optional ingredients are not particularly limited thereto.Besides them, enzymes, such as proteases, lipases, cellulases, andamylases; bleaching agents, such as sodium percarbonate; bleachingactivators, such as tetraacetyl ethylenediamine may be dry-blended asseparate granules in the granular detergent composition of the presentinvention. The optional ingredients are not particularly limited, andthey may be blended so as to give desired compositions suitable fortheir purposes.

The granular detergent composition for washing clothes of the presentinvention has a bulk density of from 0.7 to 1.2 g/cm³, preferably from0.7 to 1.0 g/cm³. Even if the dosage (weight) were the same, the higherthe bulk density, the lower the volume per cycle. For this reason, thehigher the bulk density, the better. However, some care is neededbecause too high a bulk density may cause to lower solubility. Here,when a total amount of Composition (A), Composition (B), and Composition(C) in the entire granular detergent composition is preferably from 70%by weight to 99% by weight, more preferably from 80% by weight to 99% byweight, the standard amount of dosage can be lowered remarkably. Studieshave been made to prepare blending compositions taking intoconsideration the incorporation of perfume ingredients, fluorescentdyes, and enzyme granules, and optionally bleaching agents and bleachingactivators in addition to Composition (A), Composition (B), andComposition (C).

Also, in the present invention, it is preferred that ingredients otherthan the builder granules, the enzyme granules, the bleaching agentgranules, and the bleaching activator granules are contained in onegranule. In particular, known high-density detergent granules comprisingnon-soap anionic surfactants, nonionic surfactants, zeolites, alkalizingagents, and backbone agents such as alkali metal carbonates andamorphous alkali metal silicates, and carboxylate polymers may beformulated in the detergent composition without treatments. Thesegranules may be prepared employing presently known methods in accordancewith the preparation conditions depending upon the compositions to beprepared. Examples of the methods for producing high-density detergentsinclude the methods disclosed in Japanese Patent Laid-Open Nos.61-69897, 61-69899, 61-69900, 5-209200, and DE19529298, of which thedisclosures are incorporated herein by reference. In addition, a methodfor obtaining a detergent composition with an even higher density may bereferred to W095/26394, of which the disclosure is incorporated hereinby reference.

The present invention will be more specifically explained of thefollowing working examples, without intending to restrict the scope ofthe present invention thereto.

The physical properties of products obtained in the working examples aremeasured by the following methods.

(1) Amount of Materials Having Ion Capturing Capacity

The ion capturing ability is measured by the following different methodsin accordance with a case where the materials used having a metal ioncapturing capacity are ion exchange materials and a case where thematerials are chelating agents.

A metal ion capturing capacity and a calcium ion capturing capacity aremeasured by the methods described above. Incidentally, the ion capturingcapacity of the metal ion capturing agents are expressed by CEC (calciumion exchange capacity) as in the same manner as in alkali metalsilicates. In addition, the DH water hardness is measured byion-coupling plasma method (ICP method).

(2) Average Particle Size and Particle Size Distribution of CrystallineAlkali Metal Silicates

The average particle size and the particle size distribution aremeasured by using a laser scattering particle size distributionanalyzer. Specifically, about 200 ml of ethanol is poured into ameasurement cell of a laser scattering particle size distributionanalyzer (“LA-700,” manufactured by HORIBA Ltd.), and about 0.5 to 5 mgof the crystalline alkali metal silicate is suspended in ethanol. Next,while subjecting the obtained ethanol suspension to ultrasonic waveirradiation, the mixture is agitated for one minute, to therebysufficiently disperse the crystalline alkali metal silicate. Thereafter,the resulting mixture is subjected to an He-Ne laser beam (632.8 nm)irradiation to measure diffraction/scattering patterns. The particlesize distribution is obtained from the diffraction/scattering patterns.The analysis is made based on the combined theories of Fraunhoferdiffraction theory and Mie scattering theory. The particle sizedistribution of the suspended particles in the liquid is measured withinthe size range of from 0.04 to 262 μm. The average particle size is amedian diameter of the particle size distribution.

Preparation Example 1 (Crystalline Alkali Metal Silicate A)

To 1000 parts by weight of No. 2 sodium silicate (SiO₂/Na₂O=2.5), 55.9parts by weight of sodium hydroxide and 8.5 parts by weight of potassiumhydroxide were added, followed by stirring using a homomixer to therebydissolve sodium hydroxide and potassium hydroxide. To this solution,5.23 parts by weight of finely dispersed anhydrous calcium carbonate and0.13 parts by weight of magnesium nitrate hexahydrate were added, andthe components were agitated by using a homomixer. A given amount of themixture was transferred into a nickel crucible and baked in the air at atemperature of 700° C. for one hour, followed by rapid cooling. Theresulting baked product was powdered, to give Crystalline Alkali MetalSilicate A in the present invention. This powder had an ion exchangecapacity (CEC) as high as 305 CaCO₃ mg/g. Here, the average particlesize of Crystalline Alkali Metal Silicate A was 22 μm. Also, thecomposition and CEC of the crystalline alkali metal silicate thusobtained were as follows:

xM₂O•ySiO₂ •zMe_(m)O_(n) •wH₂O,

wherein

M₂O: Na₂O, K₂O [K/Na=0.03].

y/x: 1.8.

Me_(m)O_(n): CaO, MgO [Mg/Ca=0.01].

z/x: 0.02.

CEC: 305 CaCO₃ mg/g.

Preparation Example 2 (Amorphous Aluminosilicate)

Sodium carbonate was dissolved in ion-exchanged water, to prepare anaqueous solution with 6% by weight concentration. 132 g of the aboveaqueous solution and 38.28 g of a sodium aluminate aqueous solution(conc. 50% by weight) were placed in a 1000-ml reaction vessel equippedwith baffles. 201.4 g of a solution of No. 3 liquid glass diluted withtwice the amount of water were added dropwise to the above mixedsolution by under vigorous agitation at a temperature of 40° C. over aperiod of 20 minutes. Here, the reaction speed was optimized byadjusting the pH of the reaction system to 10.5 by blowing a CO₂ gasthereinto. Thereafter, the reaction system was heated up to atemperature of 50° C. and stirred at 500° C. for 30 minutes.Subsequently, an excess alkali was neutralized by blowing a CO₂ gasthereinto, and the pH of the reaction system was adjusted to 9.0. Theobtained neutralized slurry was filtered under a reduced pressure usinga filter paper (No. 5C, manufactured by Toyo Roshi Kaisha, Ltd.). Thefiltered cake was rinsed with water in an amount of 1000-folds that ofthe cake, and the rinsed cake was filtered and dried under theconditions of 105° C., 300 Torr, and 10 hours. Further, the dried cakewas disintegrated, to give an amorphous aluminosilicate powder in thepresent invention. Incidentally, the sodium aluminate aqueous solutionwas prepared by the steps of adding and mixing 243 g of Al(OH)₃ and298.7 g of a 48% by weight NaOH aqueous solution in a 1000 mlfour-necked flask, heating the mixture to a temperature of 110° C. withstirring, and maintaining at that temperature for 30 minutes to dissolvethe components.

From the results of atomic absorption spectrophotometry and plasmaemission spectrochemical analysis, the resulting AmorphousAluminosilicate had the following composition: Al₂O₃=29.6% by weight;SiO₂=52.4% by weight; and Na₂O=18.0% by weight (1.0 Na₂O•Al₂O₃•3.10SiO₂). In addition, the calcium ion capturing capacity (CEC) was 185CaCO₃ mg/g, and the oil-absorbing capacity was 285 ml/100 g. The contentof the microporous capacity having a microporous diameter of less than0.1 μm was 9.4% by volume in the entire micropores, and the content ofthe microporous capacity having a microporous diameter of 0.1 μm or moreand 2.0 μm or less was 76.3% by volume in the entire micropores. Thewater content was 11.2% by weight.

EXAMPLE 1

Preparation of Builder Granules (I)

3.0 parts by weight of a zeolite (4A-type; average particle size: 3 μm;CEC=280 CaCO₃ mg/g, manufactured by Tosoh Corporation), 1.0 part byweight of an acrylic acid-maleic acid copolymer (trade name: “SOKALANCP-5,” manufactured by BASF; weight-average molecular weight: 70,000;CEC=380 CaCO₃ mg/g), and 2.5 parts by weight of sodium sulfate wereadded to prepare an aqueous slurry of 50% by weight solid content. Theresulting slurry was spray-dried using a counter-current flow spraydrier, to give Spray-Dried Granules L with a water content of 5% byweight of the dead weight. Thereafter, 6.9 parts by weight ofSpray-Dried Granules L, 15.0 parts by weight of Crystalline Alkali MetalSilicate A prepared in Preparation Example 1, 5.0 parts by weight ofAmorphous Aluminosilicate prepared in Preparation Example 2, and 0.5parts by weight of Fluorescent Dye S (trade name: “WHITEX SA,”manufactured by Sumitomo Chemical Company Ltd.) were supplied in aLödige Mixer (Matsuzaka Giken Co., Ltd., equipped with a jacket). Thecomponents were agitated while keeping the jacket temperature at 70° C.Subsequently, the above components were subjected to further granulationby blending in advance at 70° C. to prepare a mixture comprising 9.0parts by weight of a polyoxyethylene alkyl ether (trade name: “NONIDETR-7,” manufactured by Mitsubishi Chemical Corporation, an alkylene oxideadduct, of which the alkyl moiety has 12 to 15 carbon atoms, and theethylene oxide moiety has a molar number of 7.2) and 4.5 parts by weightof palmitic acid (trade name: “LUNAC P-95,” manufactured by KaoCorporation), and spraying the resulting mixture to the above componentsin the mixer. Here, a part or a whole part of the fatty acid wasneutralized to form a salt of the fatty acid on the surface ofCrystalline Alkali Metal Silicate A having a high alkalizing ability.Further, the resulting granules were surface-coated for improving thepowder properties by adding 3.0 parts by weight of the zeolite (4A-type)to the surface. The builder granules (I) thus obtained had a bulkdensity of 0.85 g/cm³ and an average particle size of 448 μm.

Preparation of Anionic Surfactant Granules (I)

0.6 parts by weight of a polyoxyethylene alkyl ether (trade name:“EMULGEN 108,” manufactured by Kao Corporation, of which an ethyleneoxide moiety has an average molar number of 6.0 and an alkyl moiety has12 carbon atoms), 14.0 parts by weight of a sodium linearalkylbenzenesulfonate of which alkyl moiety has 12 carbon atoms, 4.0parts by weight of a sodium alkyl sulfate of which alkyl moiety has 14carbon atoms, 2.0 parts by weight of an acrylic acid-maleic acidcopolymer (trade name: “SOKALAN CP-5,” manufactured by BASF,weight-average molecular weight: 70,000, CEC=380 CaCO₃ mg/g), 10.0 partsby weight of a zeolite (4A-type, average particle size: 3 μm, CEC=280CaCO₃ mg/g, manufactured by Tosoh Corporation), 0.4 parts by weight of apolyethylene glycol (manufactured by Nippon Shokubai Co., Ltd.,weight-average molecular weight: 8,000), 5.0 parts by weight of sodiumcarbonate, 2.0 parts by weight of potassium carbonate, 4.0 parts byweight of JIS No. 1 Sodium Silicate, 4.0 parts by weight of sodiumsulfate, 1.0 part by weight of sodium sulfite, and 0.1 parts by weightof Fluorescent Dye T (trade name: “CINOPEARL CBS-X,” manufactured byCiba Geigy AG) were added to prepare an aqueous slurry of 50% by weightsolid content. The resulting slurry was spray-dried using acountercurrent flow spray drier, to give Spray-Dried Granules M with 6%by weight of water content of the dead weight. 50.1 parts by weight ofSpray-Dried Granules M were then supplied in a High-Speed Mixer(manufactured by Fukae Powtec Corp.). While agitating at roomtemperature, the spray-dried granules were subjected to granulation bygradually spraying 0.5 parts by weight of the polyoxyethylene alkylether (trade name: “EMULGEN 108”), previously heated to 70° C., to thespray-dried granules. Further, the resulting granules weresurface-coated for improving the powder properties by adding 3.0 partsby weight of the zeolite (4A-type) to the surface. The anionicsurfactant granules (I) thus obtained had a bulk density of 0.76 g/cm³and an average particle size of 438 μm.

Preparation of Detergent of Inventive Product 1

43.9 parts by weight of the builder granules (I) prepared above, 53.1parts by weight of the anionic surfactant granules (I) prepared above,1.3 parts by weight of protease granules (granules of trade name:“ALKALI PROTEASE K-16” disclosed in Japanese Patent Laid-Open No.5-25492, of which the disclosure is incorporated herein by reference, 10APu/g), 0.5 parts by weight of cellulase granules (granules of tradename: “ALKALI CELLULASE K” disclosed in Japanese Patent Laid-Open No.63-264699, of which the disclosure is incorporated herein by reference,800 u/g), and 1.0 part by weight of lipase granules (granules of tradename: “LIPOLASE 100T,” manufactured by NOVO Nordisk Bioindustry LTD.)were supplied in a V-type blender. While the components were agitatedand blended, 0.2 parts by weight of a perfume were sprayed to thegranules for providing them with a fragrance, to give 100.0 parts byweight of the detergent of Inventive Product 1.

Preparation of Detergent of Comparative Product 1

6.9 parts by weight of Spray-Dried Granules L, 50.1 parts by weight ofSpray-Dried Granules M, 15.0 parts by weight of Crystalline Alkali MetalSilicate A prepared in Preparation Example 1, 5.0 parts by weight ofAmorphous Aluminosilicate prepared in Preparation Example 2, and 0.5parts by weight of Fluorescent Dye S were supplied in a Lödige Mixer(Matsuzaka Giken Co., Ltd., equipped with a jacket). While agitating atroom temperature, the above components were subjected to furthergranulation by adding 9.6 parts by weight of a polyoxyethylene alkylether mixture and 4.5 parts by weight of palmitic acid (trade name:“LUNAC P-95”) previously blended at 70° C., the polyoxyethylene alkylether mixture comprising 9.0 parts by weight of trade name: “NONIDETR-7” (manufactured by Mitsubishi Chemical Corporation) and 0.6 parts byweight of trade name: “EMULGEN 108” (manufactured by Kao Corporation),and agitating the components. Further, the resulting granules weresurface-coated for improving the powder properties by adding 6.0 partsby weight of the zeolite (4A-type) to the surface. The granules ofComparative Product 1 thus obtained had a bulk density of 0.77 g/cm³ andan average particle size of 445 μm.

97.0 parts by weight of the granules of Comparative Product 1, 1.3 partsby weight of the protease granules (granules of trade name: “ALKALIPROTEASE K-16,” disclosed in Japanese Patent Laid-Open No. 5-25492), 0.5parts by weight of the cellulase granules (granules of trade name:“ALKALI CELLULASE K”) and 1.0 part by weight of the lipase granules(granules of trade name: “LIPOLASE 100T”) were supplied in a V-typeblender. While the components were agitated and blended, 0.2 parts byweight of a perfume were sprayed to the granules for providing them witha fragrance, to give 100.0 parts by weight of the detergent ofComparative Product 1.

The detergency of each of the detergents of Inventive Product 1 andComparative Product 1 obtained above is evaluated after each detergentis stored under the conditions of 30° C. and 60% RH for a period of 2weeks in a storage container described below. As a result, thedetergency of the detergent of Inventive Product 1 is 56.4%, and that ofthe detergent of Comparative Product 1, which has the same compositionas Inventive Product 1, is 51.2%, clearly indicating that the inventiveproduct has superior detergency to the comparative product.

Detergency Test

Detergents of Inventive Products and Comparative Products prepared abovewere used to carry out a detergency test under the following conditions:

Preparation of Artificially Stained Cloth

A sheet of cloth (#2003 calico, manufactured by Tanigashira Shoten) wasstained with an artificial staining liquid having the followingcompositions. The artificially stained cloth was produced by printingthe artificial staining liquid on the sheet of cloth by an engravurestaining machine equipped with an engravure roll coater. The process forstaining the cloth with the artificial staining liquid to prepare anartificially stained cloth was carried out under the conditions of acell capacity of a gravure roll of 58 cm³/cm² ₁ a coating speed of 1.0m/min, a drying temperature of 1000° C., and a drying period of time ofone minute. The preparation of artificially stained cloth using gravureroll coater are detailed in Japanese Patent Laid-Open No. 7-270395, ofwhich the disclosure is incorporated herein by reference.

Composition of Artificial Staining Liquid Myristic acid  1.8% by weightPalmitic acid  3.5% by weight Oleic acid  9.6% by weight Linoleic acid 1.1% by weight Triolein 12.5% by weight Squalene  6.0% by weight Eggwhite lecithin  2.0% by weight crystalline liquid Kanuma sekigyoku soil7.98% by weight Carbon black 0.02% by weight Tap water Balance

Washing Conditions

Washing of the above-mentioned artificially stained cloth with 3.5° DHwater is carried out by using turgometer at a rotational speed of 100rpm, at a temperature of 20° C. for 10 minutes, and washing was carriedout with detergents of Inventive Product 1 and Comparative Product 1.Here, the typical water hardness-increasing components (namely minerals)in the water for washing are Ca²⁺ and Mg²⁺. The ratio of Ca²⁺ to Mg²⁺ isgenerally within the range of Ca/Mg=60/40 to 85/15. In the present test,tap water is used. The unit “° DH” refers to a water hardness which wascalculated by replacing Mg ions with equimolar amounts of Ca ions.

Calculation of Detergency

Reflectivities of the original cloth and those of the stained clothbefore and after washing were measured at a wavelength of 550 nm bymeans of an automatic recording colorimeter (manufactured by ShimadzuCorporation). The detergency D (%) was calculated by the followingequation.${D = {\frac{\left( {L_{2} - L_{1}} \right)}{\left( {L_{0} - L_{1}} \right)} \times 100\quad (\%)}},$

wherein L₀: Reflectivity of the original cloth;

L₁: Reflectivity of the stained cloth before washing; and

L₂: Reflectivity of the stained cloth after washing.

Storage Container

A carton made of craft paper of a size of 640 g/m² laminated withpolypropylene to a thickness of 20 μm is formed by folding the laminatedcraft paper as shown in FIG. 3, the carton having dimensions of a lengthof 80 mm, a width of 135 mm, and a height of 110 mm, respectively. Anamount 750 g of each detergent is packed in the produced carton, and alid made of an acrylic plate which is a little larger than the open topof the carton is placed on the carton.

EXAMPLE 2

Preparation of Builder Granules (II)

2.0 parts by weight of a zeolite (4A-type, average particle size: 3 μm,CEC=280 CaCO₃ mg/g, manufactured by Tosoh Corporation), 1.0 part byweight of a sodium polyacrylate (weight-average molecular weight:10,000, manufactured by Kao Corporation), and 1.0 part by weight ofsodium sulfate were added to prepare an aqueous slurry of 50% by weightsolid content. The resulting slurry was spray-dried using acountercurrent flow spray drier, to give Spray-Dried Granules N having awater content of 5% by weight of the dead weight. Thereafter, 4.2 partsby weight of Spray-Dried Granules N, 8.0 parts by weight of CrystallineAlkali Metal Silicate B (trade name: “SKS-6,” manufactured byHoechst-Tokuyama, CEC=245 CaCO₃ Mg/g), 2.0 parts by weight of AmorphousAluminosilicate prepared in Preparation Example 2, and 0.5 parts byweight of Fluorescent Dye S were supplied in a Lödige Mixer (MatsuzakaGiken Co., Ltd., equipped with a jacket). The components were agitatedwhile keeping the jacket temperature at 70° C. Subsequently, the abovecomponents were subjected to further granulation by blending in advanceat 70° C. to prepare a mixture comprising 4.5 parts by weight of apolyoxyethylene alkyl ether (trade name: “NONIDET R-7,” manufactured byMitsubishi Chemical Corporation) and 2.0 parts by weight of apolyethylene glycol (weight-average molecular weight: 7,000,manufactured by Kao Corporation), and spraying the resulting mixture tothe above components in the mixer. Further, the resulting granules weresurface-coated for improving the powder properties by adding 3.0 partsby weight of the zeolite (4A-type) to the surface. The builder granules(II) thus obtained had a bulk density of 0.84 g/cm³ and an averageparticle size of 415 μm.

Preparation of Anionic Surfactant Granules (II)

1.0 part by weight of a polyoxyethylene alkyl ether (trade name:“EMULGEN 108,” manufactured by Kao Corporation), 20.0 parts by weight ofa sodium linear alkylbenzenesulfonate of which alkyl moiety has 12carbon atoms, 6.0 parts by weight of a sodium alkyl sulfate of whichalkyl moiety has 14 carbon atoms, 1.0 part by weight of a sodium salt ofbeef tallow fatty acid, 3.0 parts by weight of a sodium polyacrylate(weight-average molecular weight: 10,000, manufactured by KaoCorporation), 15.0 parts by weight of the zeolite (4A-type), 10.0 partsby weight of sodium carbonate, 2.0 parts by weight of potassiumcarbonate, 5.0 parts by weight of JIS No. 1 Sodium Silicate, 1.5 partsby weight of sodium sulfate, 1.0 part by weight of sodium sulfite, 0.1parts by weight of Fluorescent Dye S, and 0.2 parts by weight ofFluorescent Dye T (trade name: “CINOPEARL CBS-X,” manufactured by CibaGeigy AG) were added to prepare an aqueous slurry of 50% by weight solidcontent. The resulting slurry was spray-dried using a countercurrentflow spray drier to give Spray-Dried Granules P having 6% by weight ofwater content of the dead weight. An amount 70.0 parts by weight ofSpray-Dried Granules P thus obtained was then supplied in a High-SpeedMixer (manufactured by Fukae Powtec Corp.), and the spray-dried granuleswere subjected to granulation. Further, the resulting granules weresurface-coated for improving the powder properties by adding 4.0 partsby weight of the zeolite (4A-type) to the surface. The anionicsurfactant granules (II) thus obtained had a bulk density of 0.75 g/cm³and an average particle size of 446 μm.

Preparation of Detergent of Inventive Product 2

23.0 parts by weight of the builder granules (II) prepared above, 74.0parts by weight of the anionic surfactant granules (II) prepared above,1.3 parts by weight of the protease granules (granules of trade name:“ALKALI PROTEASE K-16,” disclosed in Japanese Patent Laid-Open No.5-25492), 0.5 parts by weight of the cellulase granules (granules oftrade name: “ALKALI CELLULASE K”), and 1.0 part by weight of the lipasegranules (granules of trade name: “LIPOLASE 100T”) were supplied in aV-type blender. While the components were agitated and blended, 0.2parts by weight of a perfume were sprayed to the granules for providingthem with a fragrance, to give 100.0 parts by weight of the detergent ofInventive Product 2.

Preparation of Detergent of Comparative Product 2

4.2 parts by weight of Spray-Dried Granules N, 70.0 parts by weight ofSpray-Dried Granules P, 8.0 parts by weight of Crystalline Alkali MetalSilicate B (trade name: “SKS-6”), 2.0 parts by weight of AmorphousAluminosilicate prepared in Preparation Example 2, and 0.3 parts byweight of Fluorescent Dye S were supplied in a Lödige Mixer (MatsuzakaGiken Co., Ltd., equipped with a jacket). While agitating at roomtemperature, the above components were subjected to further granulationby adding 5.5 parts by weight of a polyoxyethylene alkyl ether mixtureand 1.0 part by weight of a polyethylene glycol (weight-averagemolecular weight: 7000, manufactured by Kao Corporation) previouslyblended at 70° C., the polyoxyethylene alkyl ether mixture comprising4.5 parts by weight of trade name: “NONIDET R-7” (manufactured byMitsubishi Chemical Corporation) and 1.0 part by weight of trade name:“EMULGEN 108” (manufactured by Kao Corporation), and agitating thecomponents. Next, the resulting granules were surface-coated forimproving the powder properties by adding 7.0 parts by weight of thezeolite (4A-type) to the surface. The granules of Comparative Product 2thus obtained had a bulk density of 0.79 g/cm³ and an average particlesize of 437 μm.

Further, 97.0 parts by weight of the granules of Comparative Product 2,1.3 parts by weight of the protease granules (granules of trade name:“ALKALI PROTEASE K-16,” disclosed in Japanese Patent Laid-Open No.5-25492), 0.5 parts by weight of the cellulase granules (granules oftrade name: “ALKALI CELLULASE K”), and 1.0 part by weight of the lipasegranules (granules of trade name: “LIPOLASE 100T”) were supplied in aV-type blender. While the components were agitated, 0.2 parts by weightof a perfume were sprayed to the granules for providing them with afragrance, to give 100.0 parts by weight of the detergent of ComparativeProduct 2.

With respect to each of the detergents of Inventive Product 2 andComparative Product 2 prepared above, detergency is evaluated in thesame manner as in Example 1. As a result, the detergency after storageof the detergent of Inventive Product 2 is 53.4%, and that of thedetergent of Comparative Detergent 2, which has the same composition asInventive Product 2, is 48.7%, clearly indicating that the inventiveproduct has superior detergency to the comparative product.

EXAMPLE 3

Preparation of Builder Granules (III)

1.0 part by weight of a sodium alkyl sulfate of which the alkyl moietyhas 14 carbon atoms, 6.0 parts of a zeolite (4A type, average particlesize: 3 μm, CEC=280 CaCO₃ mg/g, Tosoh Corporation), 3.0 parts by weightof an acrylic acid-maleic acid copolymer (trade name: “SOKALAN CP-5”manufactured by BASF, weight-average molecular weight: 70,000, CEC=380CaCO₃ mg/g), and 2.5 parts by weight of sodium sulfate were added toprepare an aqueous slurry of 50% by weight solid content. The resultingslurry was spray-dried using a counter-current flow spray drier, to giveSpray-Dried Granules Q having a water content of 5% by weight of thedead weight. Thereafter, 13.2 parts by weight of Spray-Dried Granules Q,25.0 parts by weight of Crystalline Alkali Metal Silicate A prepared inPreparation Example 1, 6.8 parts by weight of Amorphous Aluminosilicateprepared in Preparation Example 2, and 0.4 parts by weight ofFluorescent Dye S were supplied in a Lödige Mixer (Matsuzaka Giken Co.,Ltd., equipped with a jacket) and agitated with keeping the jackettemperature at 70° C. Subsequently, the above components were subjectedto further granulation by blending in advance at 70° C. to prepare amixture comprising 12.0 parts by weight of a polyoxyethylene alkyl ether(trade name: “NONIDET R-7,” manufactured by Mitsubishi ChemicalCorporation), 6.0 parts by weight of a beef tallow fatty acid, and 0.5parts by weight of a polyethylene glycol (weight-average molecularweight: 7000, manufactured by Kao Corporation), and spraying theresulting mixture to the above components in the mixer. Here, a part ora whole part of the fatty acid was neutralized to form a salt of thefatty acid on the surface of Crystalline Alkali Metal silicate A havinga high alkalizing ability. Further, the resulting granules weresurface-coated for improving the powder properties by adding 4.0 partsby weight of the zeolite (4A-type) to the surface. The builder granules(III) thus obtained had a bulk density of 0.79 g/cm³ and an averageparticle size of 444 μm.

Preparation of Anionic Surfactant Granules (III)

9.0 parts by weight of a sodium salt of methyl ester of α-sulfosulfuricacid of which alkyl moiety has 14 carbon atoms, 3.0 parts by weight of asodium alkyl sulfate of which alkyl moiety has 14 carbon atoms, 4.5parts by weight of the zeolite (4A-type), 4.5 parts by weight of sodiumsulfate, 1.0 part by weight of sodium sulfite, and 0.1 parts by weightof Fluorescent Dye S were added to prepare an aqueous slurry of 50% byweight solid content. The resulting slurry was spray-dried using acountercurrent flow spray drier, to give Spray-Dried Granules R having6% by weight of water content of the dead weight. Thereafter, 23.5 partsby weight of Spray-Dried Granules R, 0.5 parts by weight of sodiumcarbonate, and 2.0 parts by weight of potassium carbonate were suppliedin a ribbon mixer to blend the components. The resulting mixture wassubjected to an extrusion granulation using a twin-screw type frontextrusion granulator (“PELLETER DOUBLE,” manufactured by Fuji PaudalCo., Ltd.) and made compact by forming cylindrical pellets having adiameter of 10 mm. The resulting pellets, together with 2.0 parts byweight of the zeolite (4A-type), were pulverized and granulated to carryout surface coating of the resulting granules in a flush mill(manufactured by Fuji Paudal Co., Ltd.). Coarse-grained products wereremoved from the resulting granules. The resulting anionic surfactantgranules (III) had a bulk density of 0.75 g/cm³ and an average particlesize of 466 μm.

Preparation of Detergent of Inventive Product 3

67.9 parts by weight of the builder granules (III) prepared above, 29.1parts by weight of the anionic surfactant granules (III) prepared above,1.3 parts by weight of the protease granules (granules of trade name:“ALKALI PROTEASE K-16,” disclosed in Japanese Patent Laid-Open No.5-25492), 0.5 parts by weight of the cellulose granules (granules oftrade name: “ALKALI CELLULASE K”), and 1.0 part by weight of the lipasegranules (granules of trade name: “LIPOLASE 100T”) were supplied in aribbon mixer. While agitating and blending the above components, 0.2parts by weight of a perfume were sprayed to the granules for providingthem with a fragrance, to give 100.0 parts by weight of the detergent ofInventive Product 3.

Preparation of Detergent of Comparative Product 3

25.0 parts by weight of Crystalline Alkali Metal Silicate A prepared inPreparation Example 1, 6.8 parts by weight of Amorphous Aluminosilicateprepared in Preparation Example 2, and 0.5 parts by weight ofFluorescent Dye S were supplied in a ribbon mixer, to blend thecomponents. While the components were agitated at room temperature, amixture previously blended at 70° C., the mixture comprising 12.0 partsby weight of a polyoxyethylene alkyl ether (trade name: “NONIDET R-7”manufactured by Mitsubishi Chemical Corporation), 6.0 parts by weight ofa beef tallow fatty acid, and 0.5 parts by weight of a polyethyleneglycol (weight-average molecular weight: 7000, manufactured by KaoCorporation), was added to the above components by spraying thereto.Subsequently, 13.2 parts by weight of Spray-Dried Granules Q and 23.5parts by weight of Spray-Dried Granules R were added to the above, andthe components were blended. Thereafter, the resulting mixture wassubjected to an extrusion granulation using a twin-screw type frontextrusion granulator and made compact by forming cylindrical pelletswith a diameter of 10 mm. The resulting pellets, together with 7.0 partsby weight of the zeolite (4A-type), were pulverized and granulated usinga flush mill (manufactured by Fuji Paudal Co., Ltd.) to carry outsurface coating of the resulting granules. Coarse-grained products wereremoved from the resulting granules. The resulting granules ofComparative Product 3 had a bulk density of 0.79 g/cm³ and an averageparticle size of 437 μm.

97.0 parts by weight of the granules of Comparative Product 3, 1.3 partsby weight of the protease granules (granules of trade name “ALKALIPROTEASE K-16,” disclosed in Japanese Patent Laid-Open No. 5-25492), 0.5parts by weight of the cellulase granules (granules of trade name“ALKALI CELLULASE K”), and 1.0 part by weight of the lipase granules(granules of trade name “LIPOLASE 100T”) were supplied in a V-typeblender. While agitating and blending the components, 0.2 parts byweight of a perfume were sprayed to the granules for providing them witha fragrance, to give 100.0 parts by weight of the detergent ofComparative Product 3.

With respect to each of the detergents of Inventive Product 3 andComparative Product 3 prepared above, detergency is evaluated in thesame manner as in Example 1. As a result, the detergency after storageof the detergent of Inventive Product 3 is 56.7%, and that of thedetergent of Comparative Product 3, which has the same composition asInventive Product 3, is 49.7%, clearly indicating that the inventiveproduct has notably superior detergency to the comparative product.

In addition, the detergency performance for cases where the waterhardness is harder than the water used is evaluated by carrying out adetergency test a detergent of Inventive Product 2. In a case where thewater used is 8° DH and a washing temperature is 30° C., it is foundthat the detergency is not impaired by long-term storage as compared tothe comparative products when a detergent concentration is 0.83 g/L.Also, in a case where the water used is 15° DH, a washing time is 30minutes, and a washing temperature is 40° C., it is found that thedetergency is not impaired by long-term storage as compared to thecomparative products when a detergent concentration is 2.00 g/L.Incidentally, other washing conditions are the same as above.

INDUSTRIAL APPLICABILITY

According to the high-density granular detergent composition for washingclothes of the present invention, the standard amount of dosage of thedetergent composition is remarkably reduced when compared to theconventional compact-type detergent compositions for clothes washing. Inaddition, in the high-density granular detergent composition of thepresent invention, a good detergency can be maintained even afterlong-term storage. Further, since the detergent composition isphosphorus-free, the detergent composition is less likely to causeenvironmental problems.

The present invention being thus described, it will be obvious that thesame may be varied in many ways. Such variations are not to be regardedas a departure from the spirit and scope of the invention, and all suchmodifications as would be obvious to one skilled in the art are intendedto be included within the scope of the following claims.

What is claimed is:
 1. A high-density granular detergent composition forclothes washing, the granular detergent composition having a bulkdensity of from 0.7 to 1.2 g/cm³, comprising: (A) one or more non-soapanionic surfactants; (B) one or more crystalline alkali metal silicates;and (C) one or more metal ion capturing agents other than Component (B),wherein Component (A) is added in an amount of from 10 to 50% by weight,and a total amount of Component (B) and Component (C) is from 30 to 80%by weight, wherein a weight ratio of Component (B) to Component (C) is(B)/(C)=1/15 to 5/1, and wherein 80% by weight or more of said (B)crystalline alkali metal silicate is blended in builder granules, thebuilder granules comprising said crystalline alkali metal silicate, abinder and optionally an aluminosilicate, and wherein (A) the non-soapanionic surfactant is present in the builder granules in an amount ofless than 10% by weight.
 2. The high-density granular detergentcomposition for clothes washing according to claim 1, wherein all ofsaid Component (B) is blended in said builder granules.
 3. Thehigh-density granular detergent composition for clothes washingaccording to claim 1, wherein the binder is at least one member selectedfrom the group consisting of polyoxyethylene alkyl ethers, fatty acids,fatty acid salts, and polyethylene glycols.
 4. The high-density granulardetergent composition for clothes washing according to claim 1 whereinsaid crystalline alkali metal silicates have SiO₂/Na₂O molar ratios offrom 0.5 to 2.6.
 5. The high-density granular detergent composition forclothes washing according to claim 1 wherein said builder granules havean average particle size of from 250 to 1000 μm.
 6. The high-densitygranular detergent composition for clothes washing according to claim 1wherein said crystalline alkali metal silicates have an average particlesize of from 1 to 50 μm.
 7. The high-density granular detergentcomposition for clothes washing according to claim 1 wherein saidnon-soap anionic surfactants are at least one member selected from thegroup consisting of linear alkylbenzenesulfonates, α-olefinsulfonates,α-sulfofatty acid salts, methyl ester salts of α-sulfofatty acids, alkylsulfates, alkenyl sulfates, and polyoxyethylene alkyl ether sulfates. 8.The high-density granular detergent composition for clothes washingaccording to claim 2, wherein the binder is at least one number selectedfrom the group consisting of polyoxyethylene alkyl ethers, fatty acids,fatty acid salts, and polyethylene glycols.
 9. The high-density granulardetergent composition for clothes washing according to claim 2, whereinsaid crystalline alkali metal silicates have SiO₂/Na₂ molar ratios offrom 0.5 to 2.6.
 10. The high-density granular detergent composition forclothes washing according to claim 3, wherein said crystalline alkalimetal silicates have SiO₂/Na₂O molar ratios of from 0.5 to 2.6.
 11. Thehigh-density granular detergent composition for clothes washingaccording to claim 2, wherein said builder granules have an averageparticle size of from 250 to 1000 μm.
 12. The high-density granulardetergent composition for clothes washing according to claim 3, whereinsaid builder granules have an average particle size of from 250 to 1000μm.
 13. The high-density granular detergent composition for clotheswashing according to claim 4, wherein said builder granules have anaverage particle size of from 250 to 1000 μm.
 14. The high-densitygranular detergent composition for clothes washing according to claim 2,wherein said crystalline alkali metal silicates have an average particlesize of from 1 to 50 μm.
 15. The high-density granular detergentcomposition for clothes washing according to claim 3, wherein saidcrystalline alkali metal silicates have an average particle size of from1 to 50 μm.
 16. The high-density granular detergent composition forclothes washing according to claim 4, wherein said crystalline alkalimetal silicates have an average particle size of from 1 to 50 μm. 17.The high-density granular detergent composition for clothes washingaccording to claim 5, wherein said crystalline alkali metal silicateshave an average particle size of from 1 to 50 μm.
 18. The high-densitygranular detergent composition for clothes washing according to claim 2,wherein said non-soap anionic surfactants are at least one memberselected from the group consisting of linear alkylbenzenesulfonates,α-olefinsulfonates, α-sulfofatty acid salts, methyl ester salts ofα-sulfofatty acids, alkyl sulfates, alkenyl sulfates, andpolyoxyethylene alkyl ether sulfates.
 19. The high-density granulardetergent composition for clothes washing according to claim 3, whereinsaid non-soap anionic surfactants are at least one member selected fromthe group consisting of linear alkylbenzenesulfonates,α-olefinsulfonates, α-sulfofatty acid salts, methyl ester salts ofα-sulfofatty acids, alkyl sulfates, alkenyl sulfates, andpolyoxyethylene alkyl ether sulfates.
 20. The high-density granulardetergent composition for clothes washing according to claim 4, whereinsaid non-soap anionic surfactants are at least one member selected fromthe group consisting of linear alkylbenzenesulfonates,α-olefinsulfonates, α-sulfofatty acid salts, methyl ester salts ofα-sulfofatty acids, alkyl sulfates, alkenyl sulfates, andpolyoxyethylene alkyl ether sulfates.
 21. The high-density granulardetergent composition for clothes washing according to claim 5, whereinsaid non-soap anionic surfactants are at least one member selected fromthe group consisting of linear alkylbenzenesulfonates,α-olefinsulfonates, α-sulfofatty acid salts, methyl ester salts ofα-sulfofatty acids, alkyl sulfates, alkenyl sulfates, andpolyoxyethylene alkyl ether sulfates.
 22. The high-density granulardetergent composition for clothes washing according to claim 6, whereinsaid non-soap anionic surfactants are at least one member selected fromthe group consisting of linear alkylbenzenesulfonates,α-olefinsulfonates, α-sulfofatty acid salts, methyl ester salts ofα-sulfofatty acids, alkyl sulfates, alkenyl sulfates, andpolyoxyethylene alkyl ether sulfates.